By Peter Loftus
Merck & Co. (MRK) lost another round in its effort to block a competing generic copy of its Nasonex allergy nasal spray from entering the U.S. market.
The U.S. Food and Drug Administration this month denied Merck's petition asking the agency not to approve applications by generic drug makers to sell certain proposed generic forms of Nasonex. Merck, of Whitehouse Station, N.J., had argued the FDA shouldn't approve any proposed generic copy that has a different formulation than Nasonex.
The FDA denial of Merck's petition follows a federal court ruling earlier this year finding that Apotex Corp.'s proposed generic version of Nasonex doesn't violate a Merck patent for the drug. Merck has appealed that patent ruling.
Both developments remove some obstacles to the market entry of competing generic versions of Nasonex before patent protection expires in 2018, which would hurt sales of the branded drug. The drug, which Merck obtained in its 2009 purchase of Schering-Plough, generated $960 million in sales for the first nine months of 2012.
Canada's Apotex wants to sell a generic version of Nasonex that is slightly different from the original. The proposed Apotex product would have the same active ingredient, mometasone furoate, but in a non-water formulation, whereas Merck's product has a water component.
In 2009, Merck filed a patent-infringement lawsuit against Apotex in response to Apotex's application to market the generic product. Apotex argued that its proposed product wouldn't infringe upon Merck's patent because it would be a non-water formulation of mometasone furoate.
Following an April trial in federal court in Trenton, N.J., U.S. District Judge Peter G. Sheridan in June ruled that Apotex's proposed product wouldn't infringe upon the Merck patent, though the judge upheld the patent's validity. Merck has appealed the ruling.
In July, Merck filed a so-called citizen petition asking the FDA to refrain from approving any application for a non-water version of Nasonex that relies upon clinical data for the original drug. Merck argued that the non-water version couldn't be considered as the pharmaceutical equivalent to Nasonex because there would likely be differences in how they are absorbed in the body.
Lawyers for Apotex objected to Merck's request in a November comment letter to FDA, saying there was established precedent for the agency to approve generic versions of branded drugs that contain slightly different forms of the same active ingredient.
In a Dec. 7 letter, the FDA denied Merck's petition, saying that a non-water form of mometasone could potentially be considered pharmaceutically and therapeutically equivalent to the water-based Nasonex, assuming other requirements are met.
"We were disappointed with the decision on the citizen petition," said Merck spokesman Ronald Rogers.
The FDA denial of Merck's petition doesn't amount to approval of Apotex's generic product; that review is pending.
Apotex spokesman Steve Giuli declined to comment.
Merck shares declined 38 cents to $43.85 Wednesday.
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